1. Field of the Invention
The present invention relates to a character recognizing apparatus having a pattern recognizing function using an image processing technique, and more particularly, to a method of segmenting handwritten touching numeral strings having a non-vertical segmentation line.
2. Background of the Related Art
Recognition of handwritten numeral strings is one of pattern recognizing fields which have been most actively researched, because of having various application field such as zip codes recognition, check recognition, format document recognition or the like.
It is known that the process of recognizing the handwritten numeral strings containing touching numeral strings by use of a conventional character recognizing apparatus is difficult. The touching numeral strings may be classified into a first type of which a portion of numeral stroke is touched to neighboring numeral and a second type of which the neighboring numerals are touched by means of ligature.
In particular, the method of segmenting the touching numeral strings of the first type includes a recognition-based segmentation method in which candidate segmentation points are searched from a binary image or contour line of the touching numeral string and then in the results of recognizing the sub-image segmented by the candidate segmentation point the major candidate segmentation point is regarded as a final segmentation point, and another method of segmenting the touching numeral strings according to a segmentation rule independent upon the recognizing results. Since the former method may search the stable segmentation point in relative to the latter, it is widely used.
In addition, according to the methods of segmenting the numeral strings, the touching numeral string is segmented in a vertical direction by the searched candidate segmentation points. At that time, in case the touching numeral string having any inclination is segmented in the vertical direction by the candidate segmentation point, a portion of the numeral strokes may be lost. Therefore, the touching numeral string having any inclination provides more error results than the touching numeral string having no inclination.
Meanwhile, in order to solve the above problems, a method has been proposed in which after the inclination of the numeral string is compensated the numeral string is segmented and recognized. However, the inclination for the non-inclined numeral (i.e., numeral 4) may be evaluated, thereby obtaining erroneously compensated numeral images.